Hydraulic governor



Feb. 28, 1956 w. M. KENNEDY HYDRAULIC GOVERNOR 2 Sheets-Sheet 1 Filed April 16. 1955 ATTORNEY Feb. 28, 1956 w. M. KENNEDY HYDRAULIC GOVERNOR 2 Sheets-Sheet 2 Filed April 16, 1955 ATTORNEY United States Patent HYDRAULIC GOVERNOR Wallace Murray Kennedy, Bloomfield Hills, Mich., as-

signor to General Motors Corporation, Detroit, Micin, a corporation of Delaware Application April 16, 1953, Serial No. 349,291

15 Claims. (Cl. 123-103) This invention relates to engine governors particularly of the hydraulically actuated variety. The invention aims generally toward effecting improvements in governor control units as are used in over-speed control systems in which a source of engine developed fluid pressure is regulatively applied through a centrifugally unbalanced con trol valve to a pressure responsive servo device that is operatively connected to adjust the engine throttle in the carburetor system of the engine.

In such apparatus the centrifugal governor control valve is carried by a governor shaft portion that may be integral with or a separable part rotatatively driven by the shaft of an engine accessory, usually the engine distributor. In prior art governor installations the manner of adapting the engine accessory and the construction of the governor control unit accommodated thereby have been such as to require disassembly of the accessory and of the governor unit and to require calibration or adjustment of the speed setting of the governor for installation thereof.

Accordingly, it is the principal object of the present invention to provide a novel construction for a governor control unit such that the unit may be pre-adjusted and packaged in the factory ready to be installed in the field or service garage as a working unit without requiring disassembly and adjustment or setting thereof. Another object is to adapt an existing engine accessory to accommodate a governor control unit of this character in such a manner that extensive modification of the accessory and disassembly thereof for installation of the governor unit is not required. Other objects are to provide an improved hydraulic over-speed governor which is of simple and inexpensive construction, Which is positive and reliable in operation, which employs a minimum number of parts and is possessed of a high degree of sensitivity and stability over a wide range of operating conditions.

Fig. l is a front elevation view with parts broken away and in section illustrating a governor installation on an engine lubricating oil pump in accordance with the present invention;

Fig. la illustrates the manner in which the oil pump may be adapted to receive the governor control unit shown thereon in Fig. l;

Fig. 2 is a fragmentary side elevation view with parts broken away and in section illustrating the governor adaptor structure installed on the engine lubricating oil pump of Fig. l; and

Fig. 3 is a bottom plan view with parts broken away and in section of Fig. 2.

Referring to the drawings, the present invention is illustrated in an hydraulic speed controlling system which comprises, in general, an engine lubricating oil pump 10, a centrifugal governor control unit 12 and a pressure responsive servo device 14, which may be mounted on a wall 16 of the engine crankcase 17 and is operatively connected to effect an adjustment of the throttle valve associated with the carburetor system of the engine. An oil pan 20 detachably connected to the engine crankcase 'ice forms an oil sump containing a quantity of lubricating oil, which is supplied to the pump inlet through a float type oil strainer 22 of conventional design.

The oil pump 10, which is mounted in an opening in the engine crankcase communicating with the oil sump, may be of the commonly employed high capacity gear type developing substantially full engine pressure at about /3 engine speed and comprises a generally one piece housing 24, which is formed with an enlarged open-ended lower portion 24a having a pump chamber 25 (Fig. 2) therein and an axially extending shaft 26 mounted in the pump chamber of the pump housing, and a driver gear 30 which meshes with and drives an idler gear 32 mounted on a stub shaft in the pump housing. The driver shaft 26, which extends axially through the pump housing and is rotatable therein, is adapted to be driven at its upper end from a gear on the cam shaft within the crankcase of the engine.

The pump cover 36 may be a one-piece casting having a plate or cover portion 38, a pair of axially downwardly extending spaced legs 40 and 42, which support the governor unit, and an integrally formed generally L- shaped intake conduit 44 having an arm 45 that communicates with the inlet or low pressure side of the pump through the cover plate portion 38 and another arm 46 that is suitably connected to the outlet 48 of the strainer 22 in the oil pan 20. The cover plate portion 38, which is detachably connected from the pump housing as by bolts 39, is bored and counterbored, as shown at 54) and 51, coaxially with the pump shaft 26, and has a pressure pocket 54 formed therein on the high pressure side of the pump chamber.

The pump shaft 26 extends through the pump cover portion 38 and has a fluid pressure supply path therein constituted by a diametrically transverse passage 56, which communicates with the pressure pocket 54 in the pump cover portion 38, and an axially extending passage 58 extending between the transverse passage 56 and the end of the pump shaft, substantially as shown, The end of the shaft passage 58 may be capped or plugged as by a pin 59 (Fig. 1a) which is removed when the governor control unit of the invention is installed. With the pump cover and pump shaft formed as described above, the governor control unit may be combined therewith after the pump has been installed on the engine without necessitating disassembly of the pump.

The governor control unit 12 comprises an adaptor plate 60, a governor shaft portion 62 and a centrifugally unbalanced control valve assembly 64 carried by the governor shaft 62. The governor adaptor plate 60 is a one-piece irregularly shaped casting having a plurality of upwardly extending bosses integrally formed thereon including a pair of end bosses 66 and 68, which are respectively aligned with the legs 45) and 42 of pump cover plate portion 38 and are detachably secured thereto as by bolts 6?, and a third boss 70 which is disposed between the said end bosses and is axially aligned with the pump shaft 26. The boss 74 has a shaft bore 71 therein which receives a bronze bushing 72 and provides a journal for supporting one end of the rotatable governor shaft element 62.

The governor shaft element 62 is of reduced diameter at its lower end journaled in the adaptor plate 60 and is enlarged at its opposite or upper end which has an axial end bore 74 extending therein to form a walled receptacle or socket that telescopically receives the pump shaft extension therein without the pump chamber. A separable rotative drive connection is provided between the adjacent telescoped ends of the pump shaft 26 and governor shaft 62 in the form of a slot 76 in the end of the pump shaft extension and a pin 78 which is received in the slot 76 and.

extends through the governor shaft. The pump shaft 26 may have a pair of spaced annular grooves 80, therein for a pair of O-rings 82, that serve to prevent leakage of fluid supplied to the governor from the pump shaft. The governor shaft has a diametrically extending cross-bore 86 intermediate the ends thereof and contains a plurality of staggered fluid passages therein branching from the crossbore including an inclined pressure inlet passage 88 communicating with the axial end bore 74, an axially extending outlet passage 90 communicating with the bore 71 in adaptor plate 60 and a pressure relief passage 92 formed by a notch in the side of the governor shaft at one end of the cross bore 86 whereby the pressure inlet passage 33 and the pressure outlet passage 90 may communicate with atmosphere, as will appear below.

The control valve assembly 64 comprises a valve spool or stem 94, a centrifugal fly-weight 96, a balance spring 98 and a spring tensioning nut 100. The valve spool or stem 94 is slidably fitted in the cross-bore 86 in the governor shaft and has an annular groove 102 between the ends thereof which serves to establish fluid communication between the pressure outlet passage 90 and the pressure relief passage 92, the pressure inlet passage 88 and the pressure outlet passage 90 or all three of said passages depending upon the position of the valve which is determined by the speed of the engine. A portion of the valve spool normally closing the inlet branch passage 90 may be provided with a plurality of spaced circumferential grooves 104 that serve to reduce the friction of the valve spool and cause a relatively free and positive valve movement by providing somewhat of a floating action to the spool within the cross-bore 74.

The centrifugal fly-weight 96 is bored and counterbored to accommodate a bushing 106 of synthetic rubber or the like, which serves as a torsional vibration damper, and is retained on the valve stem or spool 94 by a spring clip or washer 108 and an enlarged integrally formed head 94a on one end of the spool. The tensioning spring 93, which is located at the end of the valve spool opposite the fly-weight 96, is seated at one of its ends in a spotfaced groove or slot 110, which is formed in the surface of the governor shaft coaxial with the cross-bore 86 therein, and is seated at its other end against the spring tensioning nut 160, which is threaded on a reduced end portion of the valve spool, substantially as shown.

The governor adaptor plate has a pressure discharge passage 112 therein, which communicates at one end with the bore 71 in boss and is capped with a core plug 114 at its opposite end in the side of boss 66. A counterbored branch passage 116 communicating with passage 112 is provided in boss 66, substantially as shown, and is connected to a counterbored passage 118 in the leg 40 of the pump cover through a nipple 120 in the adjacent counterbored ends of the passages 116 and 118. An O-rong 122 is provided in a shallow counterbore in the end boss 66 in the face thereof adjacent the end face of the leg 40 to prevent fluid leakage therebetween. The connecting passage 118 communicates with an opening 124 formed in a side boss 126 at the upper end of the leg 40 adjacent the pump cover portion 38, which opening forms a discharge port from the governor and threadably receives one end of a length of connecting line or tubing 128 the other end of which is connected to the pressure responsive servo device 14. By connecting the tubing to the outer end of the discharge passage 112 in the adaptor plate, the construction of the pump cover may be somewhat simplified and the core plug 114 eliminated.

The device 14 may be a conventional pressure diaphragm structure, one side of the diaphragm 130 of which forms a flexible wall for a pressure chamber within the housing 132 of the device and is adapted to be exposed to the fluid pressure regulatably applied thereto through the governor control unit. The other side of the diaphragm may be exposed to atmosphere and is operatively connected to the engine throttle valve. The

servo device 14 is shown mounted interiorly of the engine from a wall of the engine crankcase, but may be mounted at the intake manifold adjacent the engine throttle valve, if desired. In either event only a single short length of hydraulic connecting tube is employed in the entire speed control system. It will be further noted that the inaccessible interior location of the governor control unit within the engine presents unauthorized personnel from tampering with the governor speed setting.

The weight of the governor fly-weight 96, the adjusted compressive strength of the balance or tensioning spring 98, and the speed of revolution of the governor shaft 62 determines the extent that the valve spool 94 moves to govern the flow of fluid under pressure from the oil pump to the pressure responsive device 14.

With the parts of the control system in the normal position shown, starting of the engine causes rotation of the pump shaft 26 and causes engine lubricating oil pressure to be supplied in an hydraulic path or circuit from the pressure side of the pump chamber 25 to the pressure pocket 54 in the pump cover, the pressure supply passages 56 and 58 in the pump shaft, the axial end bore 74 and diagonal pressure inlet passage 88 in the governor shaft and then to the crossbore 86 in which the valve stem 94 is normally positioned to block the inner end of the pressure inlet branch passage. With the valve stem in the normal position shown, the annular groove 102 therein registers with the pressure relief slot or passage 92 and the pressure outlet branch passage 90, so as to relieve fluid pressure on the pressure diaphragm 14 and thus to reference the system to atmosphere.

Upon an increase in the speed of the pump shaft 26 to a value suflicient to cause the centrifugal fiyweight 96 and valve stem 94 to move radially outwardly of the governor shaft against the force of the balance spring 98 on the valve stem, the valve stem groove 102 will be moved initially into momentary registry with the inner end of all three passages 88, 90 and 92 in the governor shaft, and then will be finally moved into registry with the pressure inlet and outlet branch passages 88 and 90, when substantially full lubricating oil pressure will be applied through the pressure outlet passage to the diaphragm pressure chamber in the pressure operated throttle actuating device 14. The momentary application of pressure from the pressure inlet passage 88 to both the pressure relief slot or passage 92 and the pressure outlet passage 90 limits the sudden increase of pressure in the diaphragm chamber so as to prevent over-shooting and consequent hunting that otherwise would obtain.

What is claimed is:

1. In combination with an engine accessory having a housing and an engine driven shaft rotatable in the housing, a support having a journal in a portion thereof detachable from said housing, a rotatable governor element having a plurality of passages therein, one end of said rotatable governor element being journaled in said support, a separable rotative drive connection between the other end of said rotatable governor element and said shaft and a centrifugally unbalanced spring biased valve slidably mounted in said rotatable governor element between the said passages therein for controlling communication therebetween.

2. In combination with an engine accessory having a housing, a cover for said housing and an engine driven rotatable shaft extending through said cover without said housing, a support having a journal in a portion thereof detachable from said housing cover, a rotatable governor element journaled at one end in said support, a separable rotative drive connection between the other end of said rotatable governor element and said shaft and a centrifugally unbalanced spring biased governor valve in said governor element.

3. In combination with an engine accessory having an engine driven shaft rotatably mounted therein, a governor control unit comprising a centrifugally unbalanced spring biased control valve and a rotatable shaft-like body portion for said valve, said valve body portion being coaxial and telescopically connected with said rotatably driven by said accessory shaft.

4. In combination with an engine accessory having a housing and an engine driven shaft rotatably mounted in said housing, a support having a journal in a portion thereof detachable from the said housing, a rotatable governor element being journaled in said support and its other end coaxial and telescopically connected with said shaft, a separable rotative drive connection between said governor element and said shaft and a centrifugally unbalanced spring biased cross-valve slidably mounted in said rotatable governor element between the said passages therein for controlling communication therebetween.

5. In combination with an engine accessory having a housing, a pressure chamber in said housing and an engine driven shaft rotatably mounted in said housing, said shaft having a passage therein communicating with said pressure chamber, a support having a journal in a portion thereof detachable from said housing, a rotatable governor element journaled at one end in said support, a separable rotative drive connection between the other end of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore therein and a plurality of passages branching from said bore including a pressure inlet passage communicating with said shaft passage and a pressure outlet passage, and a centrifugally unbalanced spring biased cross-valve slidably mounted in the said cross-bore of said rotatable governor element for controlling communication between the said passages therein.

6. In combination with an engine accessory having a housing, a pressure chamber in said housing and an engine driven shaft rotatably mounted in said housing, said shaft having a passage therein communicating with said pressure chamber, a support having a journal in a portion thereof detachable from said housing, a rotatable governor element journaled at one end in said support, a separable rotative drive connection between the other end of said rotatable governor element and said shaft, sealing means between adjacent ends of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore therein and a plurality of passages branching from said bore including a pressure inlet passage communication with said shaft passage and a pressure outlet passage, and a centrifugally unbalanced spring biased cross-valve slidably mounted in the said cross-bore of said rotatable governor element for controlling communication between the said passages therein.

7. In combination with an engine driven pump having a housing, a pump chamber in said housing and an engine driven shaft rotatably mounted in said housing, said housing having a separate inlet passage and outlet passage therein communicating with said pump chamber, said shaft having a fluid passage means therein communicating with said pump chamber, a support having a journal in a portion thereof detachable from said housing, a rotatable speed governor element journaled at one end in said support and telescopically receiving said shaft at its other end, a separable rotative drive connection between the adjacent ends of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore extending therethrough and a plurality of fluid pressure passages branching from said cross-bore including a fluid pressure inlet passage communicating with said pressure inlet passage and said pressure outlet passage, a centrifugally unbalanced spring biased control valve slidably mounted in the said cross-bore of said rotatable governor element for controlling fluid communication between said passages therein, said support having a discharge port therein connecting with said fluid pressure outlet passage in said rotatable governor ele- 6 ment, the said outlet passage of said governor element being independent of said inlet passage and outlet passage of said pump housing.

8. In combination with an engine lubricating oil pump and an oil sump, said pump having a housing, a pump chamber in said housing, said housing having a separate fluid inlet and pressure outlet passage communicating with the pump chamber a fluid intake conduit extending between said oil sump and communicating with said fluid inlet passage of said pump housing and an engine driven shaft rotatably mounted in and having an end portion extending without said housing, said shaft having a fluid pressure supply passage therein communicating with said pump chamber, a governor adaptor member detachable from said pump housing and having a journal therein spaced from the end of said housing, a rotatable speed governor element. journaled at one end in said adaptor member and telescopically receiving the extension of said shaft in its other end, fluid sealing means and a separable rotative drive connection between the telescoped ends of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore therein and a plurality of fluid passages branching from said crossbore including a fluid pressure inlet passage communicating with said pump shaft passage and a fluid pressure outlet passage, and a centrifugally unbalanced spring biased control valve slidably mounted in the said crossbore in said rotatable governor element for controlling fluid communication between the said passages therein, said adaptor member having a discharge passage therein communicating with said fluid pressure outlet passage in said rotatable governor element, the said outlet passage of said governor element being independent of said inlet passage and outlet passage of said pumphousing.

9. In combination with an engine lubricating oil pump and an oil sump, said pump having a housing, a pump chamber in said housing, said housing having a separate fluid inlet and pressure outlet passage communicating with the pump chamber a fluid intake conduit extending between said oil sump and communicating with said fluid inlet passage of said pump housing and an engine driven shaft rotatably mounted in and having an end portion extending without said housing, said shaft having a fluid pressure supply passage therein connecting with said pump chamber, a governor adaptor member detachable from said pump housing and having a journal therein spaced from the end of said housing, a rotatable speed governor element journaled at one end in said adaptor member and telescopically receiving the extension of said shaft in its other end, sealing means and a separable rotative drive connection between the telescoped ends of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore therein and a plurality of fluid passages branching from said cross-bore including a fluid pressure inlet passage communicating with said pump shaft passage, a fluid pressure outlet passage and a pressure relief passage and a centrifugally unbalanced spring biased control valve slidably mounted in the said crossbore in said rotatable governor element for controlling fluid communication between the said passage therein, said adaptor member having a discharge passage therein communicating with the said fluid pressure outlet passage in said rotatable governor element, the said outlet passage of said governor element being independent of said inlet passage and outlet passage of said pump housing.

10. In combination with an engine lubricating oil pump and an oil sump, said pump having a housing, a pump chamber in said housing, said housing having a separate fluid inlet passage and outlet passage therein communicating with said pump chamber, a pump cover having an intake conduit extending between said oil sump and communicating with said fluid inlet passage of said pump housing, a pair of spaced support legs depending from each cover and a pump shaft rotatably mounted in said housing, said shaft having an end portion extending without said pump cover and a fluid pressure supply passage in said end portion communicating with said pump chamsaid adaptor member and having an axially formed opening in its other end for receiving the extension of said pump shaft therein, sealing means on said shaft extension in said governor element, a pin and slot rotative drive connection between the adjacent ends of said rotatable governor element and said shaft, said rotatable governor element having a cross-bore therein and a plurality of fluid passages branching from said cross-bore including a fluid pressure inlet passage connecting with said shaft extension passage through said end opening in said rotatable governor element, a fluid pressure outlet and a pressure relief passage between said cross-bore and the exterior of said rotatable governor element, and a centrifugally unbalanced spring biased control valve slidably mounted in the said cross-bore in said rotatable governor element for controlling fluid communication between said passages, said adaptor member having a pressure discharge passage therein communicating with said fluid pressure outlet passage in said rotatable governor element, the said outlet passage of said governor element being independent of said inlet passage and outlet passage of said pump housing.

11. In combination with an engine accessory having a housing, a pressure chamber in said housing and an engine driven shaft rotatably mounted in said housing, said shaft having fluid passage means in an end thereof in communication with said pressure chamber and extending without said housing, support means having a journal in a portion thereof adapted to be attached to said housing, a rotatable speed governor element journaled in said attachable portion and adapted to receive the extension of said accessory shaft and to be rotatively driven thereby, said governor element having a pressure inlet passage therein adapted to communicate with said shaft passage means, a pressure outlet'passage and a centrifugally unbalanced spring biased control valve disposed between said passages for controlling communication therebetween.

12. In combination with an engine driven accessory having a housing, a pressure chamber in said housing, a cover for said housing and a shaft in said housing rotatively driven at one end from said engine and having fluid passage means in the other end thereof communicating with said pressure chamber, the said other end of said shaft extending through said housing cover and being adapted to receive and rotatively drive a centrifugally unbalanced spring biased speed governor control valve unit, and a plug adapted to seal the said fluid passage means in the extension of said shaft and to be removed therefrom when said governor control valve unit is connected to be driven by said shaft.

13. In combination, an engine having a throttle, a fluid pressure hydraulic system including a fluid sump and an engine driven pump having a housing with a pump chamber and a separate inlet passage and outlet passage therein communicating with the pump chamber and a pump shaft rotatable in the housing, a support having a journal in a portion thereof detachable from said housing, a

rotatable speed governor element having an inlet passage communicating with the pump chamber and an outlet passage, one end of said rotatable governor element being journaled in said support, a separable rotative drive connection between the other end of said rotatable governor element and said pump shaft, and a centrifugally unbalanced spring biased control valve slidably mounted in said rotatable governor element between the said passages therein controlling fluid communication therebetween, a fluid pressure responsive device having a part operatively connected to said engine throttle and a fluid carrying part connected to the outlet passage of said governor element, the said outlet passage of said governor element being independent of said inlet passage and outlet passage of said pump.

14. The combination, with a pump having a housing defining a pump chamber therein, of a governor adaptor structure including a first part forming a detachable cover for said pump chamber and having a pair of spaced support legs depending therefrom and a second part detach ably connected to said legs of said first part, said first part having a shaft bore therein and a depressed portion on the chamber side thereof adjacent said shaft bore, said second part having an opening extending part way into a portion thereof forming a journal therein coaxial with said shaft bore in said first part and an outlet passage communicating with said journal opening.

15. A governor control unit adapted to be driven by the shaft of a rotating agency comprising, in combination, a rotatable valve body having an axially extending opening in one end thereof adapted to receive the shaft of a rotating agency, a cross-bore extending generally transversely therethrough, an inlet passage extending between the said axially extending end opening and said cross-bore and an outlet passage communicating with said cross-bore;

and a centrifugally unbalanced control valve including a valve stem extending through and in slidable contact with said cross-bore and having an annular groove between the ends thereof controlling communication between said inlet passage and outlet passage of said valve body, a weight on one end of said stem Without said cross-bore and a balance spring on the other end thereof contacting said stem and said valve body.

References Cited in the file of this patent UNITED STATES PATENTS 1,811,850 Huff June 30, 1931 2,412,289 Pugh et al Dec. 10, 1946 2,415,510 Mallory Feb. 11, 1947 2,433,954 Lapsley Ian. 6, 1948 

